1. The problem statement, all variables and given/known data Two single frequency coherent microwave beams are directed from the same point towards a concave mirror. One beam is incident parallel to the principal axis of the mirror, 0.06m from the axis. The other beam passes through the focal point before striking the mirror. The strongest possible signal that can be produced by the combination of the two beams is detected where they meet, 0.3m away from the mirror. f=0.2m Calculate: 1) how far from the mirror do the two beams originate 2) how far below the axis do they meet 3) minimum possible frequency of the microwaves c= 3x10^8 m/s 2. Relevant equations 1/f= 1/u + 1/v m=v/u c=fλ 3. The attempt at a solution 1) In this question I used the 1/f= 1/u +1/v formula. I got the answer of 0.6m 2) In this case I used the m= v/u formula. Knowing that the size of the object is 0.06m (or rather its 0.06m away form principal axis) I got the answer of 0.03m 3) Not 100% sure about this one although first I found the distance from f to the source. I used trigonometry to find the hypotenuse. I got a triangle of lengths 0.06m, 0.4m, and 0.404m. I figured that the 0.404m side is 1 wavelength longer than the 0.4m side. So I found wavelength of the wave. Then I used the last formula and I found the answer to be around 7.5x10^10 Hz. Could somebody tell me whether im right or wrong because I have no access to the solution.